feat(ytmusic): music#Playlist fixes and additions (#138)

* feat: add MusicEditablePlaylistDetailHeader parser

* feat: more info in `DropdownItem`

* fix: empty `year` value in `MusicDetailHeader`

* fix(ytmusic#Playlist): header err w/ own playlists

* feat: include reload continuation in `MusicShelf`

* feat(ytmusic): add getSuggestions() to Playlist

src/parser/classes/DropdownItem.ts

@@ -7,8 +7,9 @@ class DropdownItem extends YTNode {
 
   label: string;
   selected: boolean;
-  value?: number;
+  value?: number | string;
   iconType?: string;
+  description?: string;
   endpoint?: NavigationEndpoint;
 
   constructor(data: any) {
@@ -19,6 +20,8 @@ class DropdownItem extends YTNode {
 
     if (data.int32Value) {
       this.value = data.int32Value;
+    } else if (data.stringValue) {
+      this.value = data.stringValue;
     }
 
     if (data.onSelectCommand?.browseEndpoint) {
@@ -28,6 +31,10 @@ class DropdownItem extends YTNode {
     if (data.icon?.iconType) {
       this.iconType = data.icon?.iconType;
     }
+
+    if (data.descriptionText) {
+      this.description = new Text(data.descriptionText).toString();
+    }
   }
 }